1. The Field of the Invention
The present invention generally relates to virtual private networks. In particular, the present invention relates to systems and methods for enabling both the exchange of data and the execution of software applications remotely via a virtual private network. More particularly, one aspect of the present invention relates to various communication features, including protocol features, that enable and enhance the use of the User Datagram Protocol (UDP) in facilitating the communications.
2. The Related Technology
In today's business world, many businesses protect their data from unauthorized access by installing firewalls into their network infrastructure. Typically, a firewall prevents unidentified users from accessing network data from a remote location. Although firewalls are generally very beneficial for enabling a business to have more control over who accesses its network data, they also have the undesirable consequence of disconnecting mobile professionals from critical and urgent business information when they are away from the office or otherwise unable to gain local access to the network data.
To enable a mobile professional to access business information from a remote location, some businesses have installed virtual private networks (VPNs) between the business and designated remote locations, such as from a professional's home or satellite office. The function of a VPN is to open a secure connection between the business network and a designated remote location through the business firewall. Although beneficial for providing remote access to network data, a VPN often requires the installation of expensive hardware and/or software at the business network and sometimes at the remote location.
In typical VPN arrangements, a user communicates with a business network from a remote location through a VPN tunnel. At each end of the VPN tunnel is a VPN node. At the business network, one of the VPN nodes straddles the business network's firewall. Network data is transmitted through the firewall at the VPN node and through the VPN tunnel to the user. It may also be possible for a remote business to communicate with the business network through a second VPN tunnel between the two VPN nodes.
VPN hardware and software employ encryption technology and other security features at the VPN nodes to ensure that data transmitted through a VPN tunnel is not intercepted and that the user or remote business is authorized to access the business network data. The benefits of a VPN, however, are limited to discrete, remote locations where the appropriate VPN software and/or hardware is installed. Accordingly, VPNs do not currently provide users with mobile remote access to network data stored behind business firewalls. In particular, conventional VPN does not readily enable a user to access network data from a telephone while commuting in a moving vehicle, or from various other mobile devices, including pagers, personal digital assistants (“PDAs”), and laptop computers.
With regard to the aforesaid mobile devices, it is highly desirable in today's mobile society to provide enhanced connectivity between such devices and a remote location, such as a business network at the user's place of employment. The ability for such mobile devices to remotely and securely exchange both data and applications with the business network greatly enhances both their utility and value, particularly for mobile professionals and others who spend a significant amount of time away from the office. As already described, typical VPN configurations do not readily enable such mobile remote connectivity.
In addition, there is a need to maintain the bandwidth usage for data transmission to remote wireless devices to a minimum. The data transport mechanisms associated with the conventional TCP/IP systems currently use greater bandwidth than is desirable. Systems and methods that reduce the bandwidth usage would therefore represent a significant advance in the field.
Further complicating the secure transfer of data between a remote device and the business network is the fact that the remote device and business network may employ respectively differing communication protocols for transmitting data. For example, an e-mail application locally based in a business network may employ the Messaging Application Programming Interface (“MAPI”) protocol for exchanging e-mail messages to network users. A remote device, such as a PDA, however, may use the differing Post Office Protocol (“POP”) for retrieving, sending, and reading e-mail. Without resolution, the incongruity of the two protocols renders communication between the remote and local devices impossible.
In view of the foregoing, a need currently exists for providing a means by which secure communication can be transacted between a local host device and a remote device without the attendant problems discussed above. In addition, such a means should provide for the ability to exchange data and/or share applications between the host and remote device even in cases where differing protocols are respectively employed.